Thank you for your question. God is needless of our worship, however, in order to reach proximity and intimacy with Him, we need to worship and praise Him. The reward is for us and not because He needs worship. It is like rewarding a child for practicing to read fluently. You can read and do not need him to read. But for the sake of his or her goodness you encourage them to read and reward them when they do.
May you always be successful